Rotary toothbrush



Aug 26, 1930 c. MCLELLAN 1,774,031

ROTARY TOOTHBRUSH rusa July 13, 1929 Patented Aug. 26, 1,930

a (Hermanns MnnnLAN, ors1oux.c1'rY,-Iow.a

j ROTARY 'roo'.rBBRUsn Appiieation ined Juiyr' 13, 1929. A' Serial No.erases'.

Myinvention relates to rotary toothbrushes and has for its object toprovide a toothbrush of simple, durable and inexpensive construction. f

5 The invention ving a casingiproviding ahood .for covering a portionVofthe brush and a handletobe grasped by the hand of the operator,abrush ournalled-in the handle anda knob tobe engaged by thevtingersoic. the operator'for rotating the brush.

As already stated, itis my purpose to `provide a construction asvinexpensive as possible. However,

element in a brush of this charactennamely, the possibility of removingand replacing the brush per se from the casingwhich holds To this end,my invention contemplates providing av device in which the brush isembodied in a detachable'unit comprising the brush and afshank byy meansof which the brush may be attached to the knob.

A A further 'object ofmy invention "necessarily resultingv from thelabove mentioned Objectis' that'or` providing ,ank arrangementbrushandknob may be attachedtogether in connection with the handle which inv`whi ch Ythe supports them insuch a way `that-they are journalledvwithin the handle. for rotation. Atthe same time, itzis an arrangementin whichlthe att-achinggor detaching of thebrush/may be accomplished ina very simple manner. To this end,my invention contemplates .the use ofa snap linkdriving connectionbetween the brushand the knob andthe hidingof said driving connection within the handle of the brush. T v

`A further object to 'provideA a ldevice ofy 40 the above characterjinwhich the ysnap* driving connection betweenthe two rotating; elements ofthe brush` is not required tosustain the burden of? supportinglthefbrushk and knob in axial alignment with 'each other. i To this aend, my invention rproposes .to utilize the han,-v

is embodied in a d'evicefhavanother feature is avery important`template'd are attained, as hereinafter more 'and parts lbeing' shown y'illustrate lthel construction.

my purpose to provide f and dle as a bushing'to support rotatable shaftportions of the brush and knob, respectively,

the shaft portions both: beingV oflsncient -length to give therequired-'support andthe :snap drivlng'y connection being interposedV'therebetween and-'positioned intermediatethe ends of the handle.

`Another object of my invention, is tovf'provide a` brush whichisparticularly adapted tov be cleaned and kept in asanitary condition.v

With these and other objects in view, my

"invention" consists in thel construction, ar-

rangementland combination of the various parts of my device, wherebytheobjects con- Fig. 2 is a longitudinal, sectional view of a thebrush. *iv Fig. 3 is ay similarl sectional vview ofthe -rotating assembly, the'bruvshrbeing omitted irl-elevation to further Fig. 4 is an end `viewofthe brush shank. Fig. l5 is an 'end view of the brush shank viewedfrom the socket end. Y' l Fig. Gais an end view of the knob viewed fromits'vshaft end. n s f* l 7-is`an end view of the assembledv brush `Fig.`8 isa detaiL'section'al view showing a ymodified form of'snaplinkconnection. v

Ihave 'used' the reference character 10 to indicate-l i generally lthe icasing of the f device which is constructed in one integral piece't'oform ahoo'dv 1-1 and a handle or barrel 12.`

The Qbarrelis provided 4with an axial bore,

whichisfsuiiciently smooth toform a bearing surfacefor the rotatingparts.A Between the hood 11, and barrel 12 is `formed i asquaredshoulder `13, jwhich may beconsidered 'asv one y 1 the barrel 12.v

end of the barrel 12, the other end also being squared as shown.

The brush unit comprises a cylindrical brush 14:, which is provided withthe central core yor spindle 15, on which the bristles of the brush aremounted. The spindle 15 projects from one end as at 16, where it isreceived in the shank 17 Vof the brush, which is cylindrical in form andsized to fit smoothly within thebore of the barrel 12.

The shank 17 is provided at one end with an enlarged collar` 18, formedintegrally with the shank and-adapted to engagethe shoulder 13 of thebarrel l2.

At its other end the shank 17 is provided with a' socket 18a, which ispreferably polyhedral in construction, as shown in Fig. 5. The end ofthe shank 17 is split'as atV 19 to forml two socket jaws 20, the .slotl19-allowing the jaws to spread.

Thejaws 20 are also cut away as at 21 so that the cross sectioned areawithin the circumference of the outeredgesv of the jaws is less thantheV cross sectional area-of the interior ofthe barrel`l2. The objectofthus reducingithe jaws is to allow them to spread within the barrel 12.

The knobA 22 is formed integrally with a knob shaft V23,y which-also isshaped to smoothlylitl within the'bore of the barrel 12. A shoulder 24deformedybetween the shaft 23 and knob 22, which engages the free end ofThe end. ofthe shaftf23fopposite the knob 22 is providedwith a teat 25,which is shaped to, fit snugly'within the socket 18; The socket w18 andteat 25'are formed withoneor more inclined sides, thus enlarging theircross sectional area near theinner extremity of the socket and near theendo'f the teat.

The teat is providedL with a bevelled' end face 27, which spreads thejaws 2O to allow Ithe teatto-enter the socket.v It will now be seen thata'snap construc tionis provided, `which not onlyacts as a drivingconnection between the two rotatable members, but also serves to holdthem together'against pulling apart. At the same time, when sufficientpullis exerted against the'inembers by the hands of the operator, theymay be separated for the purpose ofreplacing a brush or for cleaning,

It will be under stood that the ordinary person using a brush ofthiskind will wish to clean'the brush, at least tovrinse it,'after ,eachperiod of use. For this purposeit will be desirable to' separate theparts and to wash orrinse ,them individually. Thus the brush is, muchmore sanitary than it, would be if the part-s were not readilyseparable.

j The shaft 23and shank17ua`re journalled withinthebarrel 12 sothat/lateral support for the brushy and knob are provided. The

' snap connection'is thus relieved of' all lateral strainsand may thus'v'be constructed more each other from delicately and with much lesslength to the socket than would otherwise be necessary. The onlyfunctions of the snap connection are those of providing a. drivingconnection and yieldably holding the knob and brush together.

The shoulders 18 and 24 tend to prevent the entrance of moisture orforeign material into the barrel of the brush and thus assure smoothoperation of the brush.

It will be understood that the snap construction might be any of severaltypes. For instance, the construction shown inFig. 8 might be employed,wherein, instead of a teat that is approximately square in crosssection, a flat vfinger 30 vmay be employed, adapted to enter a slot 3 1in the end of the shank 17 and provided with a pair of lugs or the like32, adaptedto enter depressions formed for them between the jaws 20a.

The advantagesof my invention reside in its sanitary features and initssimplicity and inexpensiveness. The combination vof the sanitaryfeature, the detachability ofA the brush unit and the simplicity andsturdiness of construction are believed to be novel in Vrotarytoothbrushes.

Some changes may be made in the construction and arrangement of theparts of my invention without departing from the real spirit and purposeof my invention, and it is my intention to cover by my claims, anymodified forms ofV structure or use of mechanical equivalents, which maybe Areasonably included within their scope.

1 claim as my invention:

1. In a rotary tooth brush, a barrel serving as a handle, said'barrelhaving a longitudinal cylindrical bore extending therethrough, abrush',l a shank in which said brush is mounted, al driving memberincluding a shaft and a knob, thea shank and shaft having cylindricalportions snugly journalled in the barrel, anda separable connectionbetween the cylindrical portions, comprising projections on the ends ofthe respective cylindrical por.

tions extending longitudinally thereof into latching engagement, theprojections having non-cylindrical faces in engagement with each othertov formv a driving connection between the cylindricalk portions, saidprojection'svbeing of resilient material and the said faces beinginclinedulaterally outwardl from the cylindrical portions, so thatthe'projections must spring apart in order to move past latched tounlatched positions.A l

2. In a rotary tooth brush, a barrel serving asa handle, said barrelhaving a longitudinal cylindrical bore extending therethrough, abrush.,v al shank in which said brush is mounted', a driving memberincluding a shaft and a knob, the shaft and shank being of resilientmaterial land having cylindrical' portions journall'e'd in theb'arrel',the inner end of one f pulling apart under normal working condi' y ofsaid cylindrical portions being split to form two separated membersprovided with a.

space between them that is non-cylindrical in cross-section and has aconstricted mouth, and a teat formed on the other cylindrical portion,including an enlarged portion joined to the body of said othercylindrical portion by means of a reduced neck and receivable betweensaid spaced members to form therewith a driving connection between theshank and shaft and to latch them together against tions.

Signed this 8th day of July, 1929, in the county of Woodbury and Stateof Iowan CHARLES MGLELLAN.

